Double reject gate mechanism



Aug. 20, 1968 L. N. WILDER DOUBLE REJECT GATE MECHANISM Filed Dec. 13,1966 INVENTOR.

LESLIE N WILDER BY 8M ATTORNEYS United States Patent 3,397,779 DOUBLEREJECT GATE MECHANISM Leslie N. Wilder, San Jose, Calif., assignor toIcore Industries, a corporation of California Filed Dec. 13, 1966, Ser.No. 601,505 7 Claims. (Cl. 209-74) This invention relates to a rejectiongate mechanism, and more particularly relates to a gate mechanism havinga plurality of gate elements.

In processing containers such as cans and boxes, it is customary toprovide some inspection mechanism to determine whether the articles areonweight or offweight, whether they have a label properly positioned orsome other property. In such mechanisms, after a determination has beenmade, it is necessary that the articles be segregated into a pluralityof different paths, one representing the acce table containers andanother path representing the rejected containers. In the past it hasbeen proposed to provide a moving belt mechanism wherein a singleswinging gate is provided over the belt, the gate serving the purpose ofcausing articles to follow one path when in a closed position and followanother path when in the open position. The disadvantage of such asingle gate is that it must be of substantial width in order to effectthe rejection action. More important, depending upon the separationdesired, maximum possible deflection angle, line speed and containerspacing, it may be impossible to achieve the required separation Withoutphysical interference of the gate with either preceding or succeedingcontainers.

This is especially apparent if the gate must go through a uniform cyclefor each reject container. Hence if one reject follows another, the gatemust open to deflect the first, then return to its unoperated positionbefore again rotating to deflect the second. It is also usually desiredthat the gate not strike the container, but reach its new positionbefore the container contacts it, to avoid damage to the container, asthe gate motion is usually rapid.

In addition, since the rotational moment of inertia increases as thesquare of the gate length, a short gate is to be desired.

In accordance with the present invention, a split gate mechanism isprovided wherein the gate is divided into two segments, which may or maynot be of equal length, so that a much smaller movement of each of thetwo sections is required than the movement required for a single gate.This permits a closer spacing of the articles on the moving belt andspeeds up the segregation action.

In the drawings forming part of this application:

FIGURE 1 is a perspective view of a device embodying the presentinvention.

FIGURE 2 is a partial plan view of the segregating mechanism showing thegates in closed position with certain parts broken away for clarity ofillustration.

FIGURE 3 is a view similar to FIGURE 2 showing the gates in the openposition.

FIGURE 4 is a partial view of a modified form of gate.

Turning now to a description of the drawings by reference characters,there is shown a moving belt 5, moving to the right in the directionshown by the arrows, carrying a plurality of spaced articles, such as 7and 9. Guide members such as 11 and 13 may be employed beside the beltto insure that the articles are properly lined up for the rejectionmechanism. As the articles get to the double gate mechanism, generallydesignated 13 and hereafter described in detail, the articles will comeinto contact with the gate if the gate is closed, as is shown in FIGURES1 and 2, and the articles will be diverted by the gate into the path 15.If the gate is open, as is shown in FIGURE 3, the articles will passthrough the gate into the path 17.

3,397,779 Patented Aug. 20, 1968 which has previously been designated13, is held over the path of travel by member 19 attached to theframework of the machine, not illustrated. Member 19 supports an upperplate 21 and a lower plate 23 both of which extend out over the path ofthe moving articles. Shafts 25 and 27 are mounted for rotation in theplates 21 and 23 and carry the rejection arms 29 and 31 respectively.The ends of the two arms are preferably notched as at 33 to provide foran overlapping relationship so that they will come together and form asmooth, continuous path on one side. These notches are not necessary butare useful in securing proper alignment of the two gates. When closed,the gates form an angle with the path of travel. Typically this anglewill be about 45, although the exact optimum angle will depend to someextent on the nature of the containers, gate and belt. Further, otherfactors, such as friction, length available to achieve separation,allowable impact and the like will have an effect on the optimum angle.A bell crank 35 is attached to shaft 27 While a corresponding bell crank37 is attached to shaft 25. The two bell cranks are connected togetherby means of arm 39 and are biased into an open position by means ofspring 41. A turnbuckle 43 may be provided at the center of arm 39 forprecise positioning of the two gates. A second bell crank 45 is attachedto arm 27 and this leads through link 47 to piston rod 49 extending intoa pneumatic cylinder 51. Pneumatic cylinder 51 is provided with airtubes 53 and 55 to actuate the piston, not illustrated, therein.Normally the gates are biased open to the positions shown as 29A and31A, permitting articles to pass through the gates. However, when air isadmitted to line 53 and/or released from line 55, the parts 29 and 31will assume the positions shown in FIGURES 1 and 2, and it is obviousthat when so positioned, an article striking the gate will be divertedto path .15.

In the embodiment illustrated, the ates move in opposite directions;thus the gate segment on the side of the diversion path will push anarticle into the diversion path in the case of an article which has notbeen fully diverted at the time the gates open; this condition is oftenencountered with closely spaced articles. The opposite gate, moving awayfrom the oncoming articles, will provide no interference with articlesnot to be diverted. However, under some conditions, it may be desirableto have both gates move in the same direction, in which case both gateswould move in the same direction as the moving belt.

Although the two gates have been shown as being of equal size in FIGURES1 through 3, this is not necessary and one gate might be longer than theother, as is shown in FIGURE 4. However, in general, the gates would beof substantially equal size. FIGURE 4 illustrates an embodiment of theinvention wherein the gates are not only of unequal size but also curvedto lessen the initial impact. Here the lower gate 51 is relatively longand has a concave curve in the direction of the incoming articles. Theopposite gate 63 is relatively short and forms a continuation of thecurve of gate 61. It will be seen that the sidewise acceleration of anarticle 65 is gentle in comparison with the abrupt sidewise motionimparted by a straight gate. Tailoring of the acceleration curve ispossible by suitable design of the gate curves.

Further, although pneumatic means have been shown for actuating thegates, other means such as hydraulic or electric drives, e.g. solenoids,could be employed. Further, the exact linkage shown is not essential tothe operation of the invention and those skilled in the art willrecognize that many other linkages might be employed to open and closethe gates simultaneously. For instance, the shafts could be gearedtogether, or individual cylinders could be used to actuate each arm.Although the mechanism has been shown as suspended over the path oftravel, it might be located under the belt.

Although only a single pair of gates has been illuse trated, it isobvious that in many practical machines more than one pair of gatesmight be employed. For instance, the first pair of gates might beutilized for rejecting articles which were not of the exact weight Whilea second set of gates migh the employed for further segregating theofiweight articles into overweight and underweight articles.

It is believed apparent from the foregoing that I have provided animproved form of rejection mechanism wherein short gates are employedshortening the timespace requirements for rejecting defective articles.Fur ther, by providing short gates which sweep a relatively short path,closer container spacing may be employed and/or faster rejectionsecured.

I claim:

1. In a rejection mechanism wherein articles move over a first path andcan be diverted by a gate mechanism into a second path or continue inthe first path, the improve- 4 ment comprising a pair of mating gateelements located at substantially the center of said first path andforming an angle to the path of travel and hinged at opposite sides ofthe first path and means for moving said gate elements out of said firstpath to permit articles to pass therethrough.

2. The structure of claim 1 wherein the two gate 'elements are ofsubstantially equal length.

3. The structure of claim 1 wherein pneumatic means is employed toactuate the gates.

4'. The structure of claim 1 wherein the two gate elements turn inopposite directions.

5. The structure of claim 1 wherein at least one of the gates is curvedto predetermine the lateral acceleration curve.

6. The structure of claim 1 wherein the gate mechanism is mounted abovethe belt.

7. The structure of claim 1 wherein the angle is about References CitedUNITED STATES PATENTS ALLEN N. KNOWLES, Primary Examiner.

1. IN A REJECTION MECHANISM WHEREIN ARTICLES MOVE OVER A FIRST PATH ANDCAM BE DIVERTED BY A GATE MECHANISM INTO A SECOND PATH OR CONTINUE INTHE FIRST PATH, THE IMPROVEMENT COMPRISING A PAIR OF MATING GATEELEMENTS LOCATED AT SUBSTANTIALLY THE CENTER OF SAID FIRST PATH ANDFORMING AN ANGLE TO THE PATH OF TRAVEL AND HINGED AT OPPOSITE SIDES OFTHE FIRST PATH AND MEANS FOR MOVING SAID GATE ELEMENTS OUT OF SAID FIRSTPATH TO PERMIT ARTICLES TO PASS THERETHROUGH.